1. Field of the Invention
This invention relates to the webbing for vehicle seat belts, and more particularly to energy absorbing webbing for seat belts which, as compared with the prior art webbing, has a much greater ability to absorb energies of abrupt shocks imparted to the vehicle occupant.
2. Description of the Prior Art
The prior art webbing of this type includes that which is designed to indicate that the webbing has been too much elongated to be used upon an impact exerted thereon, or the threepoint belt in which the waist belt and the shoulder belt have different factors of permanent deformation so as to protect the human body against shocks imparted thereto. According to the prior art, as shown in FIG. 1 of the accompanying drawings, the elongation of the webbing progresses under a low load gradually increasing as indicated by the dotted line until the webbing is broken under a small rate of elongation, and such webbing has been low in energy absorbing ability for abrupt shocks imparted thereto.